08/21/2026
Smoking motor?
Usually it's a wiring problem, the wiring insulation on old motors tend to give up over time creating arcing with a distinct burning smell. It's a relatively straightforward fix, just splice in new wires, add terminals, and add a plug or connect it to a power block.
Then there's something else you didn't expect or account for, that was tonight's discovery when looking into a client's Singer 221 motor with a smoking complaint.
Lack of service is all I can think of. The inside of this motor was dirty, so very very dirty. A combination of carbon build-up from the brushes mixed in with an overabundance of old grease created a black paste substance that was on everything. It's no wonder it smoked, I'm surprised it wasn't worse.
To be clear, this isn't an owner issue, it's good practice when servicing a vintage machine to blow out the inside of the motor once in a while so there aren't any restrictions from dust, dirt, and carbon.
Thankfully, while a filthy mess to clean up, the motor didn't require new wiring and it gave me a chance to deep clean the motor commutator and armature.
We'll see how it runs later once the motor is reunited with the machine but it no longer smokes.
